This means the muscle in active without conscious thought
The muscle has a lateral connection between the muscle fibres, meaning that when active, it makes all the fibres react and contract at the same time. This is necessary so that the blood is pumped upwards into the blood vessels. A large amount of force is required so this cycle can take place. The difference between the cardiac and skeleton muscle, is that when the skeleton muscle is activated, it uses individual muscle fibres to contract. If it used all the muscle fibres like the cardiac muscle, we would find it hard to live life from day to day. Picking a glass up would be impossible: every glass would be crushed by your hand. Similarly,if you were to place a pen on paper to write a letter, you might find the pen going through the paper and the table!
The reason it is called smooth muscle is because of the way it looks under the microscope. Again this is an involuntary muscle that contracts without conscious control. Most smooth muscles can be found around the arteries, and the digestion tubes around the artery walls, all over our bodies.
You can find a mixture of both voluntary muscles and involuntary muscles within the core. These are used mainly for maintaining our posture.
These are the muscles that can be found around the bone structure in order to provide protection against breakages and fractures. They produce movement and are also able to store energy. To activate this muscle we need conscious thought so that we can send a signal to the muscle through our nervous system, ordering the muscle to contract. The skeleton muscles can be found all around the body: for example, the bicep is one of many skeletal muscles.
It is important when you write your fitness plan to have involve opposite muscles. Around our body we have muscle groups at the front and back. Most people concentrate on the muscles on the front of our bodies as these are the ones we can see in the mirror. All the front muscles have opposite muscle groups which we need both for our bodies to activate normally and to produce movement.
Just think if we only had the use of the muscles at the front of our bodies! For example, when awaking in the morning, we would need to contract our abdominals to lift our bodies out of bed. In doing so, we would place our back into an L shape. It would be impossible to fix if we didn't have the use of the latissimus dorsi, a muscle, which is located in the lower back. We would need this muscle to contract so that we can become straight again and carry on with our day. Remember a muscle can only shorten; it needs an opposite muscle to contract so it can bring us back to our original form of shape.